Methods for the manufacture of III-V semi-conducting particles, such as indium phosphide, are known in the literature. For example, U.S. Pat. No. 4,783,320 (Adamski et al, assigned to the United States of America as represented by the Secretary of the Air Force) teaches a process for the high pressure synthesis of InP using an independent temperature control of a three zone furnace incorporating a heat pipe that provides a stable temperature profile throughout the synthesis cycle. This apparatus and method disclosed in the U.S. Pat. No. 4,783,320 teaches the manufacture of InP by directly reacting the elements Indium (In) and Phosphorus (P) in the furnace at temperatures above 800° C.
U.S. Pat. No. 4,185,081 (Fauth et al, assigned to the United States of America as represented by the Secretary of the Air Force) teaches a method for manufacturing InP which is similar to the method taught in the Adamski U.S. Pat. No. 4,783,320. The U.S. Pat. No. 4,185,081 discloses the direct reaction of the elements In and P in a controlled apparatus. The apparatus utilises specific heating, cooling and pressurising to safely produce InP.
UK patent application GB2356395 (Venezia Tecnologie S.p.A) discloses a further method for the direct manufacture of InP, whereby the elements In and P are directly reacted in a closed system at temperatures above 1000° C. and a pressure of 1850-2000 bars with a constant temperature increase relevant to time.
International Patent Publication No. WO/2006/099386 (Massachusetts Institute of Technology) discloses a method for the manufacture of colloidal III-V nanoparticles. The method of manufacture comprises reacting a solution of comprises at least one source material including a group III element with a source material. The source material includes including a group V element and a reducing agent in a solvent. The solvents used in the manufacturing methods disclosed in this patent application are not high boiling solvents. The manufacture of the III-V nanoparticles is conducted at high pressures in sealed containers.
In the literature there are a number of references to the manufacture of III-V semi-conductor compounds. For example. Micic et al “Synthesis and Characterisation of InP. GaP and GaInP2, J. Phys. Chem. 1995, 99, 7754-7759, discloses a method for the manufacture and characterisation of InP, GaP and GaInP2 quantum dots. This document discloses a method for the manufacture of InP by mixing a chloro-indium oxalate complex with P(SiMe3)3 in a molar ratio of In:P 1.6:1. The authors utilise trioctylphosphine oxide (TOPO) and trioctylphosphine (TOP) in this manufacture method.
Malik et al in “Gallium Arsenide Nanoparticles: Synthesis and Characterisation”, J. Mater. Chem., 2003, 13, 2591-2595, disclose the manufacture of GaAs nanoparticles from GaCl3 and As(NMe2)3, by slowly heating at 167° C. for 7 days. The P(SiMe3)3 compounds used in this publication are highly explosive and inflammable as well as being relatively expensive.
None of the prior art discloses a simple method for the manufacture of III-V particles as disclosed herein.